i think the changes are fine. some nitpicks though:
some armor/weapon enhancements that are priced at gp instead of +1 or whatever are pretty weak. it seems too costly to have to use a major fork in order to add a piddly +1,500 gp enhancement. i'd give a limit on each kind of fork (as detailed below).
i also agree about disallowing unique items as a default ruling, though the dm could certainly change that in some cases if he/she wanted.
you should specify that swapping some abilities from one item to another might make them useless if the ability doesn't work with the item in question (such as putting the keen ability on a hammer).
also, i think the formatting should be changed, as it seems a little confusingly worded to me.
maybe it should say something like:
A resonance fork can transfer armor and weapon enhancements, armor and weapon abilities that are expressed as enhancements (the spell resistance (13) armor enhancement is counted as +1 enhancement), and armor and weapon abilities that are expressed as simple gold piece increases (the shadow armor enhancement costs an extra 3,750gp). Further, a resonance fork can transfer enchantments from other enchanted items (such as rings, wondrous items, etc). A resonance fork cannot transfer the magic of artifacts, epic magical items, legacy items, or relics.
A Minor Resonance Fork is capable of transferring the magical energies of weapons up to and including +3 and armor up to and including +4; armor and weapon abilities of up to +5,000 gp; and enchantments on non-armor/weapon items (such as rings and wondrous items) of up to 10,000 gp.
A Standard Fork is capable of transferring +6 in weapon enhancements or +8 in armor enhancements; armor and weapon abilities of up to +35,000 gp; and enchantments on non-armor/weapon items (such as rings and wondrous items) of up to 70,000 gp.
A Major Fork is capable of transferring +10 in weapon enhancements and armor enhancements; armor and weapon abilities of any price; and enchantments on non-armor/weapon items (such as rings and wondrous items) of any price.
those price limitations are off the top of my head, using the weapon enhancement cost as a baseline.
and lastly, though you don't specify it, i'm guessing that the fork can transfer *all* enchantments up to the limits provided under each kind of fork (example: a major fork could handle a +6 equivalent set of armor that had eight different +3,750 gp abilities on it).